Of all its common names, the one that fits this species best is Emerald Brochis. It is a truly beautiful species that can be found in at least two (named) naturally occurring color forms—spotted and black—in addition to the more usual emerald one. Of the three Brochis species, this is the one that has been in the hobby longest, having first been imported in the late 1930s.
As its scientific name implies, Hog-nosed Brochis has many dorsal fin rays (around 17). Although it is slightly outdone in this department by B. britskii, the latter had not yet been discovered when Hog-nosed Brochis was first described. Both species are similar-looking overall, but this one lacks the bony plate that covers the underside of the head in its close relative. It also possesses a much longer snout and is a little smaller.
Brochis species are very similar overall to Coiydoras species. However, they can be easily distinguished by their much higher number of dorsal fin rays. Brochis sp. have 1 1 or more rays (Giant Brochis possesses 15-18), while in Corydoras sp. the number rarely exceeds seven. The Giant Brochis is a relatively new addition to the hobby, first making its appearance in significant numbers during the last decade and a half of the 20th century.
Both the first common name and the synonym for this species indicate just how closely Aspidoras and Corydoras species catfish are related to each other. The main distinguishing skeletal feature between the two — but one that cannot be observed in living specimens—is the number of cranial fontanels (skull pores, openings, or “holes”): Aspidoras sp. has two, while Corydoras sp. and Brochis sp. have one. The False Corydoras is a delightful species, liberally speckled in black and with a distinctive black blotch on the dorsal fin.
Greenhump Catfish are orange beneath and iridescent green on top. The intensity of their coloration depends on lighting conditions. The long mouth ends in prominent barbels on the jaws. Greenhump Catfish resemble corydoras, although they can be distinguished at a glance by their more compressed body shape and longer dorsal fin.
[Ebook] Encyclopedia of Aquarium & Pond Fish – David Alderton (Photo by Max Gibbs)
These small, armoured catfishes are ideal inmates for the community tank, where they will swim in small groups in search of food. Corydoras, with over 100 different species from which to choose, are often the first cat-fishes to be kept. Dianema longibarbis (Porthole Catfish) and Dianema urostriata (Flagtailed Catfish) belong to the same family as the Corydoras, but grow to 14 cm (5 1/2 in).
[Ebook] The New Guide to Aquarium Fish – A comprehensive and authoritative guide to tropical freshwater, brackish, and marine fishes – Mary Bailey – Gina Sandford